Such EPDM containing compositions are well known and are described in detail in Rubber Technology Handbook, Werner Hoflnann, Oxford University Press, New York, 1980, paragraph 3.3.8, pages 93-100. Paraffinic oils are used as platicisers or softening agents in such compositions. Also compositions often referred to as thermoplastic elastomers (TPE) or also sometimes referred to as thermoplastic vulcanisates (TPV) as described in said Handbook on pages 144-150 and 154-156 comprising EPDM and a polypropylene may comprise paraffinic process oils. Examples of such compositions may be found in EP-A-1132242, GB-A-155020, U.S. Pat. No. 5,290,886 and EP-A-1028145.
The paraffinic oils commonly used in such applications are either hydroprocessed petroleum derived oils, such as the Paralux oils as supplied by Chevron Products Company or synthetic paraffin oils, for example poly-alpha olefins such as a low weight component of Poly-ethylene-propylene such as described in EP-A-1028145.
U.S. Pat. No. 4,208,310 and U.S. Pat. No. 4,134,870 describe an elastomer composition containing a paraffinic wax, which according to the description may be a Fischer-Tropsch derived wax The addition of the wax, which is solid at room temperature, results improved physical and rheological properties. EP-A-577255 describes an EPDM composition which contains an extender oil and a crystalline paraffin wax. The crystalline wax may be prepared by a Fischer-Tropsch process. The paraffinic wax has a melting point of between 60 and 100° C. and is thus solid at room temperature.
Compositions as described above are often used in automotive applications, such as parts of the interior of the automobile. There is an increasing demand for low hydrocarbon emissions of an automobile. These hydrocarbon emissions are measured by keeping a complete car at an elevated temperature and detecting any hydrocarbon emissions. In view of this development there is an increasing demand for EPDM containing compositions having a low hydrocarbon emission.